Machinery foundation



1,633,940 .lane 28 1927- R, 51. GREY MACHI NERY FOUNDATION Filed April '7, 1926 Patented June 2.8, 1927.

p nsirsnsTATEs PATENT *.OFFICE",

ROBERT RERTRAM GREY, OE LONDON, ENGLAND.

MACHINERY FOUNDATION.

Application filed April 7, 1926, Serial No. 100,213, and in Great Britain April 29, 1925.t

This invention relates to improvements in and connected with the foundations for machinery or the like which is liable to transmit vibrations and noise to the surroundings.

in connection withA foundations for such machinery it has hitherto been customary to arrange the foundation block or equivalent machinery-supporting structure so that it rests upon a layer of resilient material such as felt, cork, peator the like, the sides of the foundation block usually being kept clear of the surroundings either by an air gap or by layers of resilient material.

A serious disadvantage of this arrangement is that if after the foundation has been constructed vibration is still transmitted it is impossible to adjust the resilience of the isolating medium to suit the conditions imposed by the unbalanced forces of the machinery. The natural periodicity of the foundation remains constant after construction and is unalterable except by altering the weight of the foundation block which may involve reconstruction of the foundation block-not always practicable or desirable.

This invention provides a means of readily adjusting the resilient medium to permit the periodicity of the foundation to be readily altered in accordance with the requirements of the machine upon the foundation, thus reducing the vibration and eliminating its transmission to the surroundings.

With this object in View in accordance withl the present invention the foundation block or structure is suspended by bolts ory the like resiliently supported on springs or the like with provision for convenient adjustment.

In the accompanying drawing, Fig. l is a part section part elevation of a foundation serving to support an oil engine, and constructed according to the invention: Fig. 2 is a detail view of an alternative form.

The foundation shown includes a raft A of suitable thickness constructed at the botJ tom of an excavation. In the middle of the raft A is positioned a concrete block B in which are embedded longitudinal joists C, Cv

and transverse joists D, extending beyond the block. An oil engine X is shown as erected on the block B, being secured thereto in the usual way.

Suitably in the course of construction there is interposed between the bottom of the block B and the raft A a layer E of felt, paper or B are spaced bricksor blocks F separated from the block B yby air gaps G; resilient material may be interposed `between the block IB and the. brick-work F. From the ends of the ioists C, D extend upwardly bolts H which penetrate plates resting upon springs J which rest in turn upon pads K of resilient material supported on the brick work F. The engine being in place, the nuts L on the bolts H are screwed down until the block B is lifted bodily clear of the raft A, thus taking the weight of the block and the oil engine thereon.

In conjunction with the springs J which may be of the usual carriage type there are provided auxiliary springs M engaged by joists G, the ends of the springs M being anchored to rag bolts N, the lower ends of which are embedded in the raft A. Adjustable nuts T on the bolts N serve to controlr the upward movement of the block B.

Vertical movement of the block caused by the oil engine is taken up by the springs J and M.

Control of the periodicity of vertical vibrations of the system is effected by adjusting the nuts L and T. y

The control of horizontal movement of the block B is effected by suitable springs O interposed between the joists C and blocks S of concrete or brickwork solid with the raft A, the springs O bearing against the joists C and acting against pads P of resilient material bearing against the blocks S. The periodicity of horizontal vibrations of the system may be altered by adjustment of jacks Q interposed between the springs O and the pads P.

W'here conditions permit the foundation block B may be dispensed with andthe machine mounted directly upon the joists C, C and D.

Should the arrangement of springs or resilient material not prove satisfactory for the particular conditions obtaining, the nuts and jacks may be slacked off, thus restoring the weight of the block B to the raftA, and the pads K and P and/or the springs rearranged and the nuts and acks're-tightened to take the weight of the block B.

To absorb any reaction of the springs or resilient pads the brickwork F is isolated at its base by a layer R of suitable resilient material.

This foundation arrangement can also be utilized for the mounting of delicate instruments, devices or machinery or the like, Where Vibration from machinery or trafcor the like outside the foundation block Would interfere With the Working of the said instruments, etc., such as Wireless transmitters, recording` instruments, etc.

I claim InI a'foundation vfor machinery or the like, thecombination of a concrete raft, a foundation structure, joists embedded in and projeeting indirections at right angles to one another from said structure, supporting 15 blocks spaced laterally from said structure and supported on said raft, .tension means by which said structure is suspended, said tension means'being secured to said joists7 resilieut` means for supporting said Vtension means, said resilient means being supported by said blocks, conveniently adjustable means permitting alteration of the periodicity of Vertical `vibrations of said structure, and spring means and associated adjustable devices Ifor controlling*horizontal movements of said structure.

In .testimony whereof I havesigned my name to this specication.

ROBT. B. GREY. 

